This invention relates to the rapid and safe movement of encapsulated individuals and/or materials into and out from protective structures. Encapsulation may consist, for example, of protective garments for personnel or suitable wrappings for packages. Protective structures may consist, for example, of military collective protective systems designed to protect troops from chemical warfare attacks, buildings, aircraft, spacecraft, or even an individual protective garment. Historically, everyone concerned with collective protective structures is aware of the major logistic problems in moving people and objects in and out of shelters.
Within the scope of personnel protection against a chemically contaminated environment, such as would result from a chemical warfare attack, individual protection receives a high priority. The encapsulation of personnel in a protective garment with a face mask, respiration system, etc., is very effective. However, the garment and respiration system can produce physiological and thermal stresses in combination with limited filter capacity, thereby severely limiting and restricting the effective wear duration. In order to control and limit the wear cycle for individual protection garments in the contaminated environment increasing emphasis has been placed on collective protection shelters for longer terms.
A presently accepted method to be reasonably sure the contamination will not get into such a collective main shelter is by requiring that all entry and egress of personnel be made via an airlock system. The airlock concept requires a minimum of two doorways and a separate intermediate compartment, sufficiently large to accommodate such functions as decontamination, undressing, and storage of contaminated garments. The airlock concept also greatly increases the demand for filtered air for ventilating and purging of the airlock compartment. This additional requirement results in a major increase in the size and cost of the air purification equipment necessary to operate the collective protection system.
It is generally agreed that one of the major problems associated with present collective protection structures is the logistics of rapid and safe entry of personnel or movement of equipment or stores into shelters when exposed to chemical agents. Typically a large time interval (10 to 15 minutes) is now required per person to execute safely and completely the entry procedures for a shelter equipped with a conventional positive pressure airlock system.
A number of patents have issued on special suits or systems that disclose variations on the airlock concept. Among these are U.S. Pat. Nos. 4,302,848; 3,355,230; 2,813,022; 3,744,055; 3,439,966; 3,501,213; 3,670,718; 3,802,416 and British No. 1,000,674. However none of this prior art offers a simple, re-usable, direct and rapid entry/egress system.